Restricted Stock Units (Summary of Restricted Stock Units Issued) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Share-Based Compensation Arrangement by Share-based Payment Award [Line Item]
Share based compensation expense	$ 35,000	$ 36,000
Restricted stock
Share-Based Compensation Arrangement by Share-based Payment Award [Line Item]
Restricted stock units (in units)	953,519	839,263
Fair Value	$ 59,683	$ 59,435
Minimum \| Restricted stock
Share-Based Compensation Arrangement by Share-based Payment Award [Line Item]
Award vesting period	3 years
Maximum \| Restricted stock
Share-Based Compensation Arrangement by Share-based Payment Award [Line Item]
Award vesting period	5 years

Amount, after tax, of expense for award under share-based payment arrangement.

No definition available.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other than options grants in period fair value

+ References

No definition available.

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